A novel Cs4PW11O39Fe/Si composite material to achieve high photoelectric performance.

Here we report a novel composite material Cs 4 PW 11 O 39 Fe/Si(Cs 4 PW 11 Fe/Si), which was prepared by combination of chemical etching and hydrothermal method. This composite material displays a superior photoelectric performance. A transient photocurrent density of 0.4 mA cm−2 and a maximum surface photovoltage of 0.043 mV as well as an maximum IPCE of 80.8% were obtained, much higher than those of the pristine p-Si or Cs 4 PW 11 Fe. The solar cell device ITO/Cs 4 PW 11 Fe/p-Si/Ag presents a PCE of 1.36% with a V oc of 0.78 V and a J sc of 1.27 mA cm−2 as well as a FF of 68.5%. The improvement of the photoelectric performance results from the "mastoid" structure on the surface of material and the formation of p-n heterojunction between n-Cs 4 PW 11 Fe and p-Si. The "mastoid" structure and p-n junction are favorable to increasing light absorption and facilitating photo-generated carriers's separation and transfer. • The Cs 4 PW 11 Fe/Si composite photoelectric material was first reported. • The Keggin type transition metal substituted heteropoly compounds were first introduced into the field of solar cell • A "mastoid" morphology of Cs 4 PW 11 Fe crystal was constructed on the surface of crystal Si to increase light absorption. • The remarkably enhanced photoelectric performance of Cs 4 PW 11 Fe/Si versus the pristine p-Si or Cs 4 PW 11 Fe was found. [ABSTRACT FROM AUTHOR]